1. Chaiwoot Boonyasiriwat
3D Multisource Full-Waveform Inversion using Quasi-Monte Carlo Phase Encoding
Chaiwoot Boonyasiriwat
Jan. 7, 2010

2. Outline Introduction to Multisource Technology Phase Encoding
Multisource Full-Waveform Inversion
Quasi-Monte Carlo Phase Encoding
Numerical Results
3D SEG/EAGE Overthrust Model
Summary
Future Work
Acknowledgment 1

3. Introduction: Multisource Tech.
Migration
Delayed-shot migration (Zhang et al., 2005)
Random phase encoding (Romero et al., 2000)
Plane-wave migration (Liu et al., 2006; Shan and Biondi, 2008; Shan et al., 2009)
Full-Waveform Inversion (FWI)
Plane-wave FWI (Vigh and Starr, 2008)
Random phase encoding (Krebs et al., 2009; Zhan et al., 2009) 2

4. Single-Source Method 3

5. Linear Phase Encoding—Planewave Decomposition
Multisource Method
Linear Phase Encoding—Planewave Decomposition 4

6. Multisource Method
Random Phase Encoding 5

7. CSG vs SSG
CSG SSG 6

8. Outline Introduction to Multisource Technology Phase Encoding
Multisource Full-Waveform Inversion
Quasi-Monte Carlo Phase Encoding
Numerical Results
3D SEG/EAGE Overthrust Model
Summary
Future Work
Acknowledgment 7

9. Evaluate misfit function and compute gradient
Conventional FWI
Model No
Observed Data
Evaluate misfit function and compute gradient
Evaluate misfit function
Perturb Model No
Search criterion
Convergence criterion
Yes
Done
Yes 8

10. Evaluate misfit function and compute gradient
Multisource FWI
Model No
Encoded Data
Evaluate misfit function and compute gradient
Evaluate misfit function
Perturb Model No
Search criterion
Convergence criterion
Yes
Done
Yes 9

11. 2D Multisource FWI Krebs Method (ExxonMobil): one SSG,
random source polarity, dynamic encoding 8

12. 2D Multisource FWI Zhan Method (UTAM): multiple SSGs,
random time shift, static encoding, deblurring filter 9

13. Krebs Source Configuration
3D Multisource FWI
Krebs Source Configuration 10

14. Closely Packed Source Configuration
3D Multisource FWI
Closely Packed Source Configuration 11

15. Loosely Packed Source Configuration
3D Multisource FWI
Loosely Packed Source Configuration 12

16. Quasi-Monte Carlo Source Configuration
3D Multisource FWI
Quasi-Monte Carlo Source Configuration 13

17. Static vs Dynamic Configuration
Iteration 1 2 14

18. Outline Introduction to Multisource Technology Phase Encoding
Multisource Full-Waveform Inversion
Quasi-Monte Carlo Phase Encoding
Numerical Results
3D SEG/EAGE Overthrust Model
Summary
Future Work
Acknowledgment 15

19. 3D SEG/EAGE Overthrust Model16

20. Numerical Results
True Velocity Model 17

21. Initial Velocity Model
Numerical Results
Initial Velocity Model 18

22. Velocity Model from Static QMC
Numerical Results
Velocity Model from Static QMC 19

23. Velocity Model from Dynamic QMC
Numerical Results
Velocity Model from Dynamic QMC 20

24. Velocity Model from Krebs Method
Numerical Results
Velocity Model from Krebs Method 21

25. Outline Introduction to Multisource Technology
Multisource Full-Waveform Inversion
Numerical Results
3D SEG/EAGE Overthrust Model
Summary
Future Work
Acknowledgment 22

26. Summary
3D multisource FWI using multiple SSGs is compared with multisource FWI using one SSG.
Using multiple SSGs and a dynamic QMC phase encoding provides a better-quality velocity model than a static QMC phase encoding and Krebs method.
Theoretical speedups need to be verified.
More reliable timing results will be presented later. 23

27. Outline Introduction to Multisource Technology
Multisource Full-Waveform Inversion
Numerical Results
3D SEG/EAGE Overthrust Model
Summary
Future Work
Acknowledgment 24

28. Future Work Compare various multisource configurations.
Compare random phase encoding with plane-wave encoding.
Apply random time shifts and deblurring filter.
Apply 3D multisource FWI to field data. 25

29. Acknowledgment Sponsors of 2009 UTAM consortium
HPC: Aron Ahmadia and Mark Cheeseman
Shaheen: Iain Georgeson and Jonathan Anderson
Multisource: Ge Zhan and Wei Dai
Workstation: Benoit Marchand
KAUST: Jerry Schuster 26